Color emitted by a black body on a linear scale from 800 kelvins to 12200 kelvins, given by Planck's Law, assuming a monitor properly calibrated to sRGB color space - D65 white point - 2.2 gamma.
Colors are out of gamut below 1934 K, so those have been desaturated to fit in sRGB color space (relative mapping).
It has been done with Microsoft Excel and Adobe Illustrator.

Every 1 kelvin, a sample was computed as follow :
Temperature (K) → Planck's law → CIE 2006 2° LMS color matching functions (1nm) → sRGB color space (Relative) → Gamma 2.2 → SVG
Then the whole data set has been optimized in order to rely on gradient interpolation when no visible difference occured.